Resolution of hepatopulmonary syndrome after ligation of a portosystemic shunt in a pediatric patient with an Abernethy malformation

This report describes a case of Abernethy malformation associated with hepatopulmonary syndrome, which was resolved after shunt ligation. The clinical course indicated that hepatopulmonary syndrome can develop in Abernethy malformation in which liver function and portal pressure is normal, and liver transplantation is not the exclusive therapy for hepatopulmonary syndrome. The levels of endotoxin and endothelin 1 in the shunt blood were high, whereas those of tumor necrosis factor α and interleukin-1β were within reference range. Although pathogenesis of hepatopulmonary syndrome remains unknown, the findings in this case suggest that bacterial translocation as well as elevated endothelin 1 may play a causal role in development of hepatopulmonary syndrome.     

Neutralization of blood group A-antigen by a novel anti-A antibody: overcoming ABO-incompatible solid-organ transplantation

BACKGROUND: The major barrier to ABO-incompatible solid-organ transplantation is acute humoral rejection. It is known to be triggered by antidonor blood group A/B antibodies, which might bind to A/B-antigen on the endothelium of the graft. Various strategies to reduce antiblood group antibody by overcoming ABO-incompatible transplantation have been tried. However, antigen-suppressing procedures have not been performed. METHODS: We produced a novel anti-A antibody (K7508) by immunizing mice with salivary mucin of a blood group A individual, thereby clarifying that blood group A-antigen is expressed in endothelial cells of the liver. We investigated whether K7508 can mask A-antigen on the cells in vitro. Next, we immunized mice with A-antigen-expressing cells coated with K7508 or its Fab fragment, and measured anti-A antibody production in the mice. RESULTS: Blood group A-antigen-expressing cells, such as blood group A-red blood cells (A-RBCs) and A431 cells, coated with K7508 were not recognized by another anti-A antibody in flow cytometry, indicating that A-antigen was masked by K7508 in vitro. The A-antigen on the paraffin-embedded liver tissue was also masked by K7508. Furthermore, the production of anti-A antibody in mice immunized with A-antigen-expressing cells coated with K7508 or its Fab fragment was significantly suppressed compared to that in mice immunized with non-coated cells alone, indicating that A-antigen was neutralized by K7508 in vivo. CONCLUSIONS: The neutralization of blood group antigen by antiblood group antibody and especially its Fab fragment might represent one strategy to overcome ABO-incompatible organ transplantation.     

The role of graft and host accommodation in a hamster-to-rat cardiac transplantation model

BACKGROUND: We evaluated the importance and mechanism of graft and host accommodation in hamster-to-rat cardiac xenotransplantation models. METHODS: To evaluate graft accommodation, accommodated hamster grafts (Group 2) were transplanted to na?ve host rats treated with FK506, and compared with na?ve hamster grafts (Group 1). To evaluate host accommodation, three groups were evaluated: naive hamster hearts were transplanted to na?ve hosts treated with FK506 (Group 3: 0.5 mg/kg, Group 4: 1.0 mg/kg) and splenectomy, and compared with accommodating hosts (Group 5) with FK506 0.5 mg/kg and splenectomy. We examined graft survival, histopathology, antihamster antibodies and B-1 cells in blood. RESULTS: Graft survival in Group 2 (3.4+/-0.9 days) was not significantly different from that in Group 1 (2.8+/-0.4 days). Graft survival in Groups 4 and 5 (>30 days) was significantly prolonged compared with that in Group 3 (6.0+/-0.7 days). Histopathology of Groups 1-3 showed humoral rejection, whereas Groups 4 and 5 showed normal histology and expression of protective genes. In Groups 1-3, antihamster immunoglobulin (Ig) M and B-1 cells increased significantly compared to Groups 4 and 5, where IgM and B-1 cells remained low or were reduced. CONCLUSIONS: Host accommodation was more important than graft accommodation. Accommodating grafts expressing protective genes were rejected with an elevation of both IgM and B-1 cells. In accommodated hosts, both IgM and B-1 cells decreased, suggesting that B-1 cells may be responsible for the production of antihamster antibodies. These results suggest that sufficient suppression of B-1 cells, resulting in decreased titers of antihamster antibodies, may play an important role in host accommodation.     

Specific Antibiotic Prophylaxis Based on Bile Cultures Is Required to Prevent Postoperative Infectious Complications in Pancreatoduodenectomy Patients Who Have Undergone Preoperative Biliary Drainage

Background Preoperative biliary drainage (PBD) is associated with bacterial contamination of bile, but the effects of PBD on morbidity after pancreatoduodenectomy remain controversial. The aim of this study was to characterize bile contamination to develop successful specific antibiotic prophylactic strategies for pancreatoduodenectomy. Methods Ninety-one consecutive patients who underwent pancreatoduodenectomy for periampullary tumor were prospectively evaluated. Prophylactic antibiotics were selected based on preoperative bile cultures. Bile cultures and postoperative complications were compared in 46 patients who underwent PBD (drainage group) versus 45 patients who did not (nondrainage group). Results The incidence of positive bile cultures was higher in the drainage group (78%) than in the nondrainage group (36%) (P < 0.001). In the drainage group, positive bile cultures were frequently polymicrobial (61%) and demonstrated resistance to several antibiotics, including cefazolin (83%), cefmetazole (72%), and cefpirome (64%). Overall morbidity (30% and 22%) and infectious morbidity (13% and 11%) did not differ significantly between the drainage and nondrainage groups, respectively. Conclusions PBD had a notable influence on bile microbial contamination, including a higher rate of antibiotic resistance. Therefore, specific antibiotic prophylaxis based on bile culture is required for preventing infectious complications in pancreatoduodenectomy patients who undergo PBD.     

Intradural extramedullary ganglioneuroma associated with multiple hamartoma syndrome

A 51-year-old woman presented with a rare completely intradural and extramedullary spinal ganglioneuroma associated with multiple hamartoma syndrome and manifesting as complaints of neck pain and dizziness persisting for 8 months. Magnetic resonance imaging of the spinal cord revealed an intradural extramedullary lesion at the C1 level. She underwent right suboccipital craniectomy and C1-2 hemilaminectomy to remove the tumor. Histological examination confirmed ganglioneuroma. She also suffered from multiple facial trichilemmomas, thyroid goiter, multiple polyposis of the gastrointestinal tract, and pulmonary hamartoma indicating multiple hamartoma syndrome. These benign neoplasms were treated conservatively.     

Rapid revascularization after therapeutic parent artery occlusion for a large intracavernous carotid artery aneurysm

A 21-year-old woman presented with an unruptured large intracavernous aneurysm, which was spontaneously revascularized via unusual collateral pathways a short time after extracranial-intracranial bypass and surgical ligation of the proximal internal carotid artery. The patient had been treated for a large basilar trunk aneurysm with intraaneurysmal embolization using Guglielmi detachable coils, and an intracavernous carotid artery aneurysm treated conservatively. Two years later, the patient presented with right abducens nerve palsy, and was referred to our hospital. She had small nevi in the right forehead and eyelid. Cerebral angiography revealed enlargement of the intracavernous aneurysm. Superficial temporal artery-middle cerebral artery bypass followed by surgical carotid artery ligation were performed, and good patency of bypass and disappearance of the aneurysm were confirmed by intraoperative angiography. However, follow-up magnetic resonance angiography and cerebral angiography on the 20th postoperative day revealed revascularization of the internal carotid artery and the intracavernous carotid artery aneurysm via unusual collateral pathways. Subsequently, the recurrent aneurysm and the recanalized internal carotid artery were occluded by endovascular procedures. Histological examination of the nevus showed lack of properly organized vascular structures, and the diagnosis was angiodysplasia. The early development of unusual collateral pathway, and aneurysm formation at a young age might be related to the angiodysplasia. Revascularization is possible within a short time even in cases of intracavernous carotid artery aneurysm successfully treated with surgical ligation of the parent artery.     

Histological analysis of microbleed after surgical resection in a patient with moyamoya disease

A 65-year-old male with moyamoya disease underwent surgical resection of a microbleed simultaneously with revascularization surgery. Histological examination identified several fragile arteries surrounding the microbleed. Microbleeds detected by T2*-weighted magnetic resonance imaging are considered to be a general marker of vascular vulnerability in cerebral angiopathy with a tendency to bleeding. The microbleeds observed in patients with moyamoya disease probably originate in bleeding from the fragile arteries.